That's a very odd resolution. 256x256 would've made more sense, but I guess they couldn't spare the extra few pixels...
The datasheet is an interesting read, there is some slight Chinglishness. It only needs 4 wires to interface, two of which are for power. You can vary the frame rate by varying the supply voltage(!), and for 505 pixel clocks after each frame, the sensor lets you use the same pins as it normally outputs video on to write configuration data to it. It has a single 16-bit configuration register, which you must use at least once to set the pixel reset voltage to something other than the reset default of "do not use" 1.4v.
It is not cheap though, which is surprising given how the die is probably smaller than a lot of other cheaper sensors with much higher resolution.